1. Field of the Invention
The present invention relates to a two-way interactive system having a mechanism for matching lines of sight between interlocutors through a transmission means, and a terminal equipment and an image pickup apparatus constituting the system and, more particularly, to a counseling system which realizes a two-way interactive operation between, e.g., a doctor and a patient or a counselor and a client in remote areas through a transmission means and is mainly oriented to a one-to-one two-way interactive operation, and an apparatus constituting the system.
2. Related Background Art
Conventionally, counseling in the field of education, medical service, psychology, or the like is generally performed between interlocutors directly facing each other while establishing an intimate reliability relationship between them. In some cases, however, a person who needs counseling and a person (counselor) who has mastered a counseling technique can hardly share place and time because a natural disaster has occurred, or they are in remote areas. Along with a progress in communication technology, a system for realizing counseling between persons in remote areas is strongly demanded.
In construction of such a counseling system by using a communication technology, to ensure an intimate relationship between interlocutors and an ideal counseling environment, as in the conventional face-to-face system, it is important to match the lines of sight between the interlocutors.
A conventional image pickup apparatus for matching the lines of sight between interlocutors through a transmission line is disclosed in Japanese Patent Laid-Open No. 62-269128 (first prior art). In the first prior art, a half mirror is provided between an interlocutor and the image pickup apparatus, so that light from the interlocutor as an object is divided toward the image pickup apparatus and toward an image display apparatus. Therefore, according to the arrangement of the first prior art, the image pickup apparatus is arranged at a position offset from the display screen of the image display apparatus at which the interlocutor looks, thereby matching the optical axis of light incident in the image pickup apparatus with the line of sight of the interlocutor.
Another image pickup apparatus is disclosed in Japanese Patent Laid-Open No. 4-213287 (second prior art) in which a special display apparatus capable of selecting reflection/transmission of light is used, and an image pickup apparatus is arranged behind the display apparatus (on the opposite side of an interlocutor through the display apparatus). According to this arrangement, the line of sight of the interlocutor is directed to the display apparatus, i.e., the image pickup apparatus arranged behind the display apparatus at a position offset from the display screen of the display apparatus at which the interlocutor looks, so that the lines of sight between interlocutors can be matched each other.
A still another image pickup apparatus is disclosed in Japanese Patent Laid-Open No. 4-97633 (third prior art) in which a small-size mirror or a small-size half mirror is attached to the upper portion of a display apparatus, and the image of an interlocutor is picked up by a small-size camera with an optical axis directed to the mirror. According to this arrangement, the image of the interlocutor, which is reflected by the mirror, is picked up by the small-size camera arranged at a position offset from the display screen of a display apparatus at which the interlocutor looks. Therefore, the angle of elevation of the line of sight of the interlocutor is suppressed to 10.degree. or less, which is an allowance for line-of-sight matching in the vertical direction, so that the lines of sight between interlocutors can be matched each other.